Notes: Camera wasn't still enough to get good resolution, but the punctate surface soralia and well developed marginal soralia visible. Until recently known as P. ulophylla (as in 'Dobson'), and previously confused with P. subrudecta.

Comments

Actually I was a touch uncharitable about the photography. Apologies. Camera movement spoils the close-up, which was the main one I looked at, but the left hand photograph is not at all bad and shows the lichen clearly.

I should have added that the lichen was evidently in damp condition; it is grey when dry.
Green variant of Melanelixia glabratula (= M. fuliginosa ssp. glabratula), with glossy surface, also present in the photograph.